The technique of soil reinforcement by inclusion of geosynthetics has been subject to significant development worldwide, with direct applications in slope stabilization and earthfills over soft deposits. The use of geogrids as a soil reinforcement element is an attractive alternative, although still with very little application in Brazil. This work presents the results of an investigation into soil- geogrid interaction by means of pull-out tests. Both field and laboratory pull-out tests were carried out in order not only to make clear the pull-out mechanism but also to determine the parameters for design and analysis of reinforced soil structures. The testing equipments, specimen preparation and testing procedures are described in detail. The field pull-out tests were performed with three different types of geogrids in a research area in Jacarepagua, Rio de Janeiro. Sandy and residual soil surcharge fills of 0,5 to 2m in height were used. Details of the anchored reaction structure are also presented. The laboratory pull-out tests were performed in the geotechnical laboratory at CEDEX, in Spain, with the same types of geogrids and soils. Details of the cubical pull-out box (1m in dimensions) are presented. The influence of the type of geogrid, type of soil, confining pressure and tests procedures on the pull-out stiffness and resistance of the geogrids are discussed by analysing the results of the experimental program.